This is a note to let you know that I've just added the patch titled
x86/kprobes: Fix to identify indirect jmp and others using range case
to the 5.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
x86-kprobes-fix-to-identify-indirect-jmp-and-others-using-range-case.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From stable-owner@xxxxxxxxxxxxxxx Wed Jul 5 08:48:03 2023
From: Li Huafei <lihuafei1@xxxxxxxxxx>
Date: Wed, 5 Jul 2023 14:46:50 +0800
Subject: x86/kprobes: Fix to identify indirect jmp and others using range case
To: <stable@xxxxxxxxxxxxxxx>
Cc: <gregkh@xxxxxxxxxxxxxxxxxxx>, <mhiramat@xxxxxxxxxx>, <tglx@xxxxxxxxxxxxx>, <mingo@xxxxxxxxxx>, <bp@xxxxxxxxx>, <x86@xxxxxxxxxx>, <hpa@xxxxxxxxx>, <sashal@xxxxxxxxxx>, <peterz@xxxxxxxxxxxxx>, <linux-kernel@xxxxxxxxxxxxxxx>, <xukuohai@xxxxxxxxxx>, <natechancellor@xxxxxxxxx>, <ndesaulniers@xxxxxxxxxx>, <rostedt@xxxxxxxxxxx>, <weiyongjun1@xxxxxxxxxx>, <gustavoars@xxxxxxxxxx>, <namit@xxxxxxxxxx>, <laijs@xxxxxxxxxxxxxxxxx>, <clang-built-linux@xxxxxxxxxxxxxxxx>, <lihuafei1@xxxxxxxxxx>
Message-ID: <20230705064653.226811-7-lihuafei1@xxxxxxxxxx>
From: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
[ Upstream commit 2f706e0e5e263c0d204e37ea496cbb0e98aac2d2 ]
Fix can_boost() to identify indirect jmp and others using range case
correctly.
Since the condition in switch statement is opcode & 0xf0, it can not
evaluate to 0xff case. This should be under the 0xf0 case. However,
there is no reason to use the conbinations of the bit-masked condition
and lower bit checking.
Use range case to clean up the switch statement too.
Fixes: 6256e668b7 ("x86/kprobes: Use int3 instead of debug trap for single-step")
Reported-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/161666692308.1120877.4675552834049546493.stgit@devnote2
Signed-off-by: Li Huafei <lihuafei1@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/kernel/kprobes/core.c | 44 ++++++++++++++++++-----------------------
1 file changed, 20 insertions(+), 24 deletions(-)
--- a/arch/x86/kernel/kprobes/core.c
+++ b/arch/x86/kernel/kprobes/core.c
@@ -165,32 +165,28 @@ int can_boost(struct insn *insn, void *a
opcode = insn->opcode.bytes[0];
- switch (opcode & 0xf0) {
- case 0x60:
- /* can't boost "bound" */
- return (opcode != 0x62);
- case 0x70:
- return 0; /* can't boost conditional jump */
- case 0x90:
- return opcode != 0x9a; /* can't boost call far */
- case 0xc0:
- /* can't boost software-interruptions */
- return (0xc1 < opcode && opcode < 0xcc) || opcode == 0xcf;
- case 0xd0:
- /* can boost AA* and XLAT */
- return (opcode == 0xd4 || opcode == 0xd5 || opcode == 0xd7);
- case 0xe0:
- /* can boost in/out and absolute jmps */
- return ((opcode & 0x04) || opcode == 0xea);
- case 0xf0:
- /* clear and set flags are boostable */
- return (opcode == 0xf5 || (0xf7 < opcode && opcode < 0xfe));
- case 0xff:
- /* indirect jmp is boostable */
+ switch (opcode) {
+ case 0x62: /* bound */
+ case 0x70 ... 0x7f: /* Conditional jumps */
+ case 0x9a: /* Call far */
+ case 0xc0 ... 0xc1: /* Grp2 */
+ case 0xcc ... 0xce: /* software exceptions */
+ case 0xd0 ... 0xd3: /* Grp2 */
+ case 0xd6: /* (UD) */
+ case 0xd8 ... 0xdf: /* ESC */
+ case 0xe0 ... 0xe3: /* LOOP*, JCXZ */
+ case 0xe8 ... 0xe9: /* near Call, JMP */
+ case 0xeb: /* Short JMP */
+ case 0xf0 ... 0xf4: /* LOCK/REP, HLT */
+ case 0xf6 ... 0xf7: /* Grp3 */
+ case 0xfe: /* Grp4 */
+ /* ... are not boostable */
+ return 0;
+ case 0xff: /* Grp5 */
+ /* Only indirect jmp is boostable */
return X86_MODRM_REG(insn->modrm.bytes[0]) == 4;
default:
- /* call is not boostable */
- return opcode != 0x9a;
+ return 1;
}
}
Patches currently in stable-queue which might be from stable-owner@xxxxxxxxxxxxxxx are
queue-5.10/x86-kprobes-update-kcb-status-flag-after-singlestepping.patch
queue-5.10/x86-kprobes-fix-to-identify-indirect-jmp-and-others-using-range-case.patch
queue-5.10/x86-kprobes-fix-jng-jnle-emulation.patch
queue-5.10/x86-kprobes-retrieve-correct-opcode-for-group-instruction.patch
queue-5.10/x86-kprobes-use-int3-instead-of-debug-trap-for-single-step.patch
queue-5.10/x86-kprobes-do-not-decode-opcode-in-resume_execution.patch
queue-5.10/x86-kprobes-identify-far-indirect-jmp-correctly.patch
queue-5.10/kprobes-x86-fix-fall-through-warnings-for-clang.patch
queue-5.10/x86-kprobes-move-inline-to-the-beginning-of-the-kprobe_is_ss-declaration.patch
